A study of configuration for silicon based Intermediate Trackers (IT) July-12-2005 Eunil Won Korea University

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A study of configuration for silicon based
Intermediate Trackers (IT) July-12-2005Eunil
WonKorea University
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Outline

• GLD software/simulation activity in Korea
• Configuration optimization of barrel IT
• Endcap IT first thought

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Software/Simulation

• A. Miyamoto visited Korea and gave 2 days
  tutorials (02-Jun 03-Jun)
• - 10 participants from Korea
• - Event generation/fast sim./full sim. (Geant4)
• Now we are at the end-user level and slowly
  moving forward to be developers (ex full sim.
  analysis now can deal with data with calorimeter
  off. J.Lee)
• All the plots I show today are based on his
  tutorials (thanks to A. Miyamoto)

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Roles of IT (Barrel)

• Improve momentum resolution by adding high
  precision points at large distance from IP
  (between VTX and TPC)
• Help pattern recognition in linking the tracks
  from TPC to VTX
• Help in the efficient reconstruction of long
  lived particles

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• The performance of tracking detectors can
  ultimately be tested from
• - recoil mass distribution of ee?ZH

LCWS05 (Tim Barklow)
Recoil Mass (GeV)
Recoil Mass (GeV)
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GLD Default Geometry (vtx/tracking only)
TPC

• IT (as in gld_v1.dat and C codes)
• spatial resolution 10 mm
• 4 layers (561 mm Silicon strip)
• r9 cm (innermost), 30 cm (outermost)
• half z 18.5 cm (innermost), 62 cm (outermost)
• cosqlt0.9

CAD drawing by S.K.Park
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With and W/O IT
Geant4/single muon _at_ (cosq0)
s/pT2 (GeV)-1
TPC only
TPCVTX
s/pT2 sampling term multiple scattering term
TPC only 10.9 x 10-5 6 x 10-4
TPCVTX 4.37 x 10-5 7 x 10-4
TPCITVTX 3.87 x 10-5 7 x 10-4
TPCITVTX
default goal(?) 5x10-5 (GeV)-1
H. Ha
1 GeV

• Without IT 3.9 x 10-5 (GeV)-1 (high momentum
  limit)
• With IT 4.4 x 10-5 (GeV)-1

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Number of layers vs. resolution
Geant4/single muon _at_ (cosq0)
s/pT2 (GeV)-1
2 layer option 4 layer (default) 5 layer
H. Ha
4 layer (default) is probably enough?
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We also tried...

• Varying
• position resolution (10 mm to 20 mm)
• outermost layer _at_ 37 cm
• changing the thickness from 561 mm to 300 mm

and checked the momentum resolution, but did not
find significant changes
So far, the default configuration seems to be
good (caution at the level of the study with
single muons)
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ee- ? ZH, ZZ Study (ongoing)
GLD default configuration - input mH 120 GeV
PYTHIA Geant4
ee?ZH
ee?ZZ
Y.I.Kim
We have been (and will be) working on roles of IT
in terms of physics ...
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Endcap Option
At present, we do not have endcap trackers

• Do we need it?
• If so, how many layers?
• What type of sensors?
• Where do we want to put them?
• Ill not be answering questions on the above
  today but will list questions and things to do...

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LCWS05 (Tim Barklow)
Physics and endcap detectors

• e/- veto down to 3.2 mrad in presence of very
  large ee- pair background
• Useful in general to suppress gg ? ff
  background. Takes on added importance given that
  the SUSY parameter space consistent with Dark
  Matter density includes region with nearly
  degenerate

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Tesla Option (from Tesla TDR)

• Three innermost layers pixels
• Four outer layers strip
• Endcap covers down to 7o (GLD barrel IT covers
  down to 25.8o)

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GLD Geometry (as in gld_v1.dat, maybe partially)
TPC
VTX
260 cm (150 cm for TESLA)
Endcap Calorimeter
IT
Is this completely empty? signal cables support
structure?
CAD drawing by S.K.Park
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Cross sectional View (GLD, zoomed)

• option 1 change barrel IT (same length) H.
  Park

• option 2 Tesla-like version?

CAD drawing by S.K.Park
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Cross sectional View (GLD, zoomed)

• option 1 change barrel IT (same length) H.
  Park

• option 2 Tesla-like version?

CAD drawing by S.K.Park
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CAD drawing by S.K.Park/H. Park (Tesla-like
version)
Z (cm) R (cm)
Layer 1 20 14
Layer 2 35 17
Layer 3 50 25
Layer 4 65 32
Layer 5 90 32
Layer 6 115 32
Layer 7 140 32
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Works to be done for Endcap RD

• Should it be a mixture of pixel and strip?
  (similar to Tesla)
• Have endcap IT in the simulation software
• - software organization)
• Study the best configuration for endcap IT
• - number of layers
• - geometry (change of barrel IT design needed?)
• Radiation hardness ? (requires background study)

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Summary

• Understanding of simulation software for IT RD
  in good progress
• Baseline barrel IT configuration seems OK
• Endcap IT design under consideration